Techniques for Evaluating the Fit of Removable and Fixed Prosthesis

The importance of an accurately fitting fixed prosthesis or a removable prosthesis is essential for the success of the restoration. Ill-fitting prosthesis may cause mechanical failures of the prosthesis, implant systems, or biologic complications of the surrounding tissue. There are several causes related to improper seating of the prosthesis. Some of which can be corrected and the others need to be repeated. Hence the clinician must carefully evaluate the adaptation of the prosthesis using the clinical techniques and combination of the available materials and evaluation methods to optimize the fit of prosthesis. This article reviews the various clinical methods that have been suggested for evaluating the fit of the fixed and removable prosthesis

Denture acceptance among newly rehabilitated elderly population in old age homes in South India

Introduction: Elders in old age homes are mainly those who have been abandoned by their family and have one or more physical or mental disabilities. It is a major challenge for the dental professional to plan oral health strategy for this group of patients. Aim of the Study: Aim of the present study is to observe and determine the acceptance of new dental prosthesis among the elderly residing as inmates of 3 old age homes in Mangalore City. Materials and Methods: This cross-sectional study was conducted using a survey proforma. Information regarding their experience with the new denture, 1-month, 3 months and 6 months after denture insertion was gathered. Statistical analysis of the data was done using the Chi-square test with the P < 0.05 considered significant. Results: One hundred and eighty-three residents out of a total of 400 residents in 3 old age homes were denture wearers. Among them, 101 (55.2%) were females, and 82 (44.8%) were males. Dental prosthesis whether worn regularly, discomfort, retention, cleansing of denture during a period of 1-month, 3 months and 6 months was found to be significant satisfaction with the prosthesis, denture adhesives used, food accumulation during a period of 1-month, 3 months and 6 months was found to be nonsignificant. Conclusion: The emotional makeup of the patient must be taken into consideration during the entire procedure. We must understand that the success of the prosthesis depends mainly on the patient′s confidence in the dentist rather than the quality of the prosthesis

A comparative evaluation of effect on water sorption and solubility of a temporary soft denture liner material when stored either in distilled water, 5.25% sodium hypochlorite or artificial saliva: An in vitro study

Introduction: Soft denture liners have a key role in modern removable prosthodontics since they restore health to inflamed and abused mucosa by redistribution of forces transmitted to the edentulous ridges. The most common problems encountered using soft denture liners are water sorption and solubility when in contact with saliva or storage media. These problems are associated with swelling, distortion, support of Candida albicans growth, and stresses at the liner/denture base interface that reduces the bond strength. Objective: To evaluate the water sorption and solubility of commercially available acrylic based self cure soft denture lining material (GC RELINE™ Tissue Conditioner) after immersion in three different storage media (distilled water, Shellis artificial saliva, 5.25% sodium hypochlorite disinfectant solution) at time interval of 4, 7, 11, and 15 days. Material and Methods: The study involved preparation of artificial saliva using Shellis formula. A total 45 standardized samples of the material (GC RELINE™) were prepared in disk form (15 mm in diameter and 2 mm in thickness). The study was divided into three groups with storage in Control (distilled water), Shellis artificial saliva, and 5.25% sodium hypochlorite. Samples were dried in a desiccator and weighed in the analytical balance to measure the initial weight (mg/cm2) of the disks (W1). The first groups (15 samples) were placed in 30 ml distilled water (Group A) at 37΀C, second group 30 ml of artificial saliva (Group B) and third group in 5.25% sodium hypochlorite (Group C). Disks were removed from disinfectant after 5 min and placed in 30 ml distilled water. On days 4, 7, 11, and 15, all samples were removed from their containers and reweighed to measure the weight (mg/cm2) of the disks after sorption (W2). The solubility was measured by placing the disks back in the desiccator after each sorption cycle and drying them to constant weight in the desiccator. These values were weight after desiccation (W3). Water sorption and solubility was calculated: 1. Sorption (mg/cm2) = (W2−W1)/Surface area 2. Solubility (mg/cm2) = (W1−W3)/Surface area. Statistical Analysis: Statistical Analysis was done using one way analysis of variance and the intercomparison between each group was done using Tukey′s honestly significance difference (HSD) test. Results: Within the limitations of this study it was concluded that water sorption of the GC RELINE™ soft denture liner material was highest in distilled water followed by 5.25% sodium hypochlorite and least in Shellis artificial saliva at 4, 7, and 11 day interval. However, on the 15th day, the results showed maximum water sorption in 5.25% sodium hypochlorite followed by distilled water and least in artificial saliva. The results on solubility showed highest solubility of GC RELINE soft denture liner in artificial saliva followed by distilled water and least in 5.25% sodium hypochlorite at 4, 7, 11,and 15 day interval. Discussion: The least water uptake of the soft liner in artificial saliva was due to its ionic properties and supports the theory that water uptake of these materials is osmotically driven. However, the solubility was highest in artificial saliva since it is a mix of various salts and other additives, so there is a possibility of interaction with soft denture lining material

A clinico-radiographic study to compare and co-relate sagittal condylar guidance determined by intraoral gothic arch tracing method and panoramic radiograph in completely edentulous patients

Purpose: The purpose of this study was to compare and correlate sagittal condylar guidance determined by intraoral gothic arch tracing method and panoramic radiograph in edentulous patients. Materials and Methods: Twelve completely edentulous patients were selected by the inclusion and exclusion criteria. Conventional steps in the fabrication of complete denture till jaw relation were carried out. Intraoral gothic arch tracing and protrusive interocclusal records were obtained for each patient. Protrusive interocclusal record was used to program the Hanau Wide-Vue semi-adjustable articulator, thus obtaining the sagittal condylar guidance angle. Using RadiAnt DICOM software, on the orthopantomogram obtained for each patient in the study, two reference lines were drawn. The Frankfort's horizontal plane and the mean curvature line (joining the most superior and the inferior points on the glenoid fossa curvature) were drawn. The mean curvature line was extended to intersect the Frankfort's horizontal plane, thus obtaining the radiographic sagittal condylar guidance angle. The condylar guidance angles obtained by these two methods were compared and subjected to paired t-test. Results: There was no statistically significant difference between the sagittal condylar guidance angles obtained between right and left sides with intraoral gothic arch tracing and radiographic methods (P = 0.107 and 0.07, respectively). Conclusion: Within the limitations of this study, it was concluded that the protrusive condylar guidance angles obtained by panoramic radiograph may be used for programming semi-adjustable articulators

Flexural strength of hydrogen plasma-treated polypropylene fiber-reinforced polymethyl methacrylate denture base material

Objectives: The present study aimed to evaluate flexural strength of hydrogen plasma-treated polypropylene fibers-reinforced polymethyl methacrylate (PMMA) polymer composite. Materials and Methods: One control group with no fiber reinforcement and 9 polymer composite test groups with varying fiber weight percentage (2.5, 5, and 10 Wt%) and aspect ratio (3/220, 6/220, and 12 mm/220 μm) were prepared. Flexural strength was measured using Instron. Results: All hydrogen plasma-treated polypropylene fiber-reinforced test groups obtained significantly higher flexural strength characteristics. Among the test groups, 6 mm long fibers reinforced in 10 Wt% showed superior flexural strength. Conclusion: Hydrogen plasma treatment on polypropylene fiber has a significant role in enhancing the adhesion between PMMA polymer matrix and the polypropylene fibers and thereby the flexural strength

Evaluation of accuracy of transfer of the maxillary occlusal cant of two articulators using two facebow/semi-adjustable articulator systems: An in vivo study

Aim: The aim of this study was to compare the accuracy of the angle made by Frankfort horizontal plane-occlusal plane on maxillary casts, mounted using the respective facebows on Artex Amann Girrbach and Hanau Wide-vue semi-adjustable articulators with cephalometrically derived Frankfort horizontal plane-occlusal plane angle as a control. Subjects and Methods: Maxillary casts of 30 subjects were mounted on Hanau Wide-vue and Artex Amann Girrbach semi-adjustable articulators following facebow transfer using respective facebows. The Frankfort horizontal plane-occlusal plane angles of these casts were measured using Wixey's digital angle gauge. They were also subjected to a lateral cephalogram, and the occlusal cant was measured using RadiAnt DICOM software. Statistical Analysis: Using Pearson correlation, the accuracy of the angle made by upper member of the articulator and occlusal plane of mounted maxillary casts in each of the articulator was compared to the Frankfort horizontal plane-occlusal plane angle in lateral cephalogram. Results: A mean difference of 1.9° was found between Hanau Wide-vue articulator and lateral cephalogram and a mean difference of 3.6° was found between Artex Amann Girrbach articulator and lateral cephalogram. Statistically, Pearson correlation value (r) obtained between Hanau Wide-vue and lateral cephalogram was 0.46 and between Artex Amann Girrbach and lateral cephalogram was 0.25. Conclusion: From the statistical value (r) derived, it can be inferred that the Frankfort horizontal plane-occlusal plane angle of the casts articulated on Hanau Wide-vue articulator was more accurate in comparison to that on Artex Amann Girrbach articulator

Magnets in dentistry

Magnets have generated great interest within dentistry. They have been used for various applications in orthodontics and prosthodontics. Earlier use of magnets was limited due to the unavailability of small size magnets, but after the introduction of rare earth magnets and their availability in smaller sizes, their use has increased considerably. They can be placed within prostheses without being obtrusive in the mouth. Their main use in orthodontics has been for tooth movement and in prosthodontics has been in maxillofacial prosthesis and in overdentures as retentive aids. This article reviews the types of magnets available and their application in maxillofacial prosthesis and overdentures, followed by other advantages and disadvantages